title: Quality evaluation of spaceborne SiC mirrors (II): evaluation technology for mirror accuracy using actual measurement data of samples cut out from a mirror surface.
abstract: The authors studied the quality evaluation technology of a spaceborne large-scale lightweight mirror that was made of silicon carbide (SiC)-based material. To correlate the material property of a mirror body and the mirror accuracy, the authors evaluated the mirror surface deviation of a prototype mirror by inputting actually measured coefficient of thermal expansion (CTE) data into a finite element analysis model. The CTE data were obtained by thermodilatometry using a commercial grade thermal dilatometer for the samples cut from all over the mirror surface. The computationally simulated contour diagrams well reproduced the mirror accuracy profile that the actual mirror showed in cryogenic testing. Density data were also useful for evaluating the mirror surface deviation because they had a close relationship with the CTE.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kotani
authors.forename: Tadashi
authors.initials: T
authors.lastname: Imai
authors.forename: Haruyoshi
authors.initials: H
authors.lastname: Katayama
authors.forename: Yukari
authors.initials: Y
authors.lastname: Yui
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Tange
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Kaneda
authors.forename: Takao
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Keigo
authors.initials: K
authors.lastname: Enya